הלכה על שמות 13:1

The commandment of "Tefillin" is to write four passages i.e. "Kadesh" until "l'moadah [m'yamim yamimah]"(Exodus 13:1-10); "v'haya ki yevi'acha" until "ki b'chozek yad hotziyanu Hashem mimitzrayim" (ibid 11-16); "Sh'ma" until "uvish'arekha" (Deuteronomy 6:4-9) and "v'haya im shamo'ah" until "al ha'aretz" (ibid 11:13-21) Rema: They must be written in this order, that is the order they appear in the Torah and if [the scribe] deviates from this order [the tefillin] are invalid. Ideally the arm-tefillin should be written before the head-tefillin.